Senior decision-makers come together to connect around strategies and business trends affecting utilities.


DOE Solar Desalination Prize

image credit:
John Benson's picture
Senior Consultant, Microgrid Labs

PROFESSIONAL EXPERIENCE: Microgrid Labs, Inc. Advisor: 2014 to Present Developed product plans, conceptual and preliminary designs for projects, performed industry surveys and developed...

  • Member since 2013
  • 885 items added with 597,868 views
  • Apr 8, 2021

Access Publication

The Solar Desalinations Prize is a four-round completion among developers of innovative technologies that will be used in the future for less expensive and more flexible desalination system. 

Removing salt from water takes a lot of energy! Many of the largest untapped water resources in the US and around the world cannot be cost-effectively used because of high concentrations of dissolved salts.

Water treatment processes, like reverse osmosis, are efficient when salt concentrations are low, but can’t treat high-salt waters like those that are produced from oil and gas wells, concentrated brines, and some industrial and agricultural wastewaters.

Novel thermal desalination technologies can purify water with very high salt content without dramatically increasing the amount of energy required. By using solar thermal as the energy source, desalination technologies could be used in a variety of important environments, especially in arid areas with high sun exposure, where water purification is especially important.

Note that the Semifinalists will be announced April 12, 2021. I will post a link to this announcement as a comment to this paper as soon as I identify it.



Matt Chester's picture
Matt Chester on Apr 8, 2021

Desalination is such an energy intensive process, and one that would be great to 'green'-- especially if using some sort of curtailed energy generation. It seems more of the focus in the desalination has come from the parts of the world where it's more immediately critical, like the Middle East, but I'm glad to see the DOE prioritizing it now as well

John Benson's picture
John Benson on Apr 8, 2021

Thanks for the comment, Matt.

Also very critical in California and other parts of the west. This is so for two reasons: (2) we have frequent multi-year draughts (California may be entering one now), and (2) we already make extensive use of reverse osmosis, which is extremely energy intensive (see section 2 of "Watts and Water", which is linked in the Intro). If we could replace these facilities with processes that use solar energy directly, it would help us mitigate increasing demand for electricity. I'll cover this in more detail on Tuesday's Post: "Electric Decarbonization".

Jim Stack's picture
Jim Stack on Apr 9, 2021

John, Thanks for writing about this important subject. I have read that Saudi Arabia tried desalination but it caused a salt loops by dumping the extracted salt back into the water.  

   With water pollution and very little safe drinking water left in the world I worry about trying to desalinate water. It seems to be if we switch from boiling water in fossil fuel and nuclear power plants we would have lots of water.  What do you think about that ?

John Benson's picture
John Benson on Apr 9, 2021

Thanks for the comment and question, Jim.

I try to stay close to home with new technologies. California has basically banned new reactors, but we do have at least one public utility that is part of UAMPS, and they are building the first NuScale power plant at Idaho National Lab.

We really need sea-water desalinization in many areas of California, especially around San Diego. The reverse osmosis system as used by the big Carlsbad Plant near San Diego ends up with concentrated brine that they dump back into the ocean. I don't believe this causes any environmental problems, as it ends up being quickly diluted. 

In the future we will probably need more of these, (especially if our droughts worsen) but maybe not reverse osmosis. The good news is some of the processes proposed in this paper have Zero Liquid Discharge, thus they end up with solid salts, that can be refined and used in industrial processes. See "ZLD Technology" at the bottom of page 3 and others.


John Benson's picture
John Benson on Apr 12, 2021

The site linked below describes the eight semi-finalists, which were announced today.


John Benson's picture
Thank John for the Post!
Energy Central contributors share their experience and insights for the benefit of other Members (like you). Please show them your appreciation by leaving a comment, 'liking' this post, or following this Member.
More posts from this member

Get Published - Build a Following

The Energy Central Power Industry Network is based on one core idea - power industry professionals helping each other and advancing the industry by sharing and learning from each other.

If you have an experience or insight to share or have learned something from a conference or seminar, your peers and colleagues on Energy Central want to hear about it. It's also easy to share a link to an article you've liked or an industry resource that you think would be helpful.

                 Learn more about posting on Energy Central »